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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

42294 results found.

  1. GRB041226: Swift-BAT detection of a burst
  2. GRB041223: decay of the afterglow
  3. GRB041224: ROTSE-III Optical Observations
  4. GRB 041224: near-infrared observations with REM
  5. GRB 041223: XRT afterglow spectrum and light curve
  6. GRB 041223 Fluence measured by Swift-BAT
  7. GRB041224: Swift-BAT detection of a soft burst
  8. GRB041223: optical and NIR observations with REM
  9. Swift-BAT Time History of GRB041219
  10. GRB 041219: TAROT optical observations
  11. GRB 041218: TAROT optical observations
  12. GRB 041223: J-band observations of the afterglow
  13. GRB 041223: Detection of Optical Transient with LCO40
  14. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  15. GRB 041219c: PROMPT Observations
  16. GRB041223: ROTSE-III Optical Observations
  17. GRB041223: Swift-BAT detection of a bright long burst
  18. GRB 041218: optical observations
  19. Very high activity of SGR 1806-20
  20. GRB 041219: Second Epoch WSRT Radio Observations
  21. GRB 041219: WSRT Radio Afterglow Detection
  22. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  23. GRB 041218: Optical observations
  24. GRB 041219 : optical follow-up observations
  25. GRB041220: Swift-BAT burst
  26. Deep RAPTOR observations during GRB 041219
  27. GRB 041218 Optical Observations
  28. GRB 041219 Optical Observations
  29. GRB041219c: Third Burst in One Day from Swift-BAT
  30. GRB041219: Optical Afterglow Detection
  31. GRB041219: Continued NIR Observations
  32. GRB041219b: A Swift-BAT burst
  33. GRB 041219 ,optical observation
  34. GRB 041219: Radio Afterglow Detection
  35. GRB 041218 : Radio Observations
  36. GRB 041218: R-band optical observations
  37. GRB041218: Liverpool Telescope optical observations
  38. GRB041218: optical observations
  39. GRB041219: Confirmed NIR Afterglow
  40. GRB041218: Continued P60 Optical Observations
  41. Swift-BAT detection of the bright long burst GRB041219
  42. GRB 041218: Optical Observation
  43. GRB 041219: Infrared Afterglow Candidate
  44. GRB041219, BVRcIc field calibration
  45. GRB 041219: Infrared Afterglow Candidate
  46. GRB041218, BVRcIc field calibration
  47. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  48. GRB041219: P60 Optical Observations
  49. GRB 041219 - A long GRB detected by INTEGRAL
  50. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  51. GRB 041217: PROMPT Observations
  52. GRB041218: optical observations
  53. GRB041217: optical limit 30 min after GRB
  54. GRB 041218; optical candidate
  55. GRB 041218: Optical observations
  56. GRB 041217: LCO40 Optical Observations and Possible Candidates
  57. GRB 041218 - A long GRB detected by integral
  58. GRB041217: Optical Observations
  59. GRB041217: NIR and optical observations with REM
  60. GRB041217: P60 Optical Observations
  61. GRB041217: Infrared Observations
  62. GRB041217: The First GRB Located On-Board Swift
  63. GRB041211: Faulkes Telescope continued optical monitoring
  64. Optical Transient in Lynx not a GRB
  65. Optical transient (GRB?) in Lynx
  66. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  67. GRB041211: Continued P60 Observations
  68. GRB041211: RAPTOR observations
  69. GRB041211: Ashra Prototype optical observation
  70. GRB041211, Faulkes Telescope optical observation
  71. GRB041211, BVRcIc field calibration
  72. GRB041211,optical observation
  73. GRB 041211: Infrared Observations
  74. GRB 041211: KAIT observations
  75. GRB 041211: Optical follow-up in East Asian region
  76. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  77. GRB041211: P60 optical imaging
  78. GRB970815: Discovery of Optical Afterglow
  79. Triangulation of short GRB 041116 (large error box)
  80. GRB041015: Near-Infrared observations
  81. GRB 040924: Afterglow Color
  82. GRB 041006: GETS Optical Afterglow Observation
  83. Summary of the recent bursts from SGR 1806-20
  84. GRB 041006: Optical Observations
  85. GRB041006, late-time optical photometry
  86. GRB041015, optical observation in CrAO
  87. GRB041006: RTT150 Optical Observations
  88. GRB041015 : Multi epoch optical observations
  89. GRB 041016: BOOTES-2 simultaneous observation
  90. GRB041006: RTT150 Optical Observations
  91. GRB041016,optical observation
  92. GRB 041016: Optical limits
  93. GRB 041016: Optical limits in V, R, I
  94. GRB 041016:Optical limit during first minute
  95. GRB041016: MASTER: Optical observations
  96. GRB 041015: Optical Observations at Rikubetsu
  97. GRB041006: Near Infrared observations
  98. GRB 041016: Optical limit
  99. GRB 041015 R band observations
  100. GRB040924, BVRcIc field calibration

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